As an example of drills for use in the drilling process, an indexable insert drill described in PCT International Publication No. WO 2010-137701 (Patent Document 1) has been known. The drill described in Patent Document 1 is made up of a body part having a chip discharge flute, and an insert having a cutting edge for use in cutting, which is detachably attached to the body part. The drill described in Patent Document 1 includes two inserts of the insert having a center cutting edge and the insert having an outer peripheral cutting edge.